Measurement and correlation of the solubility of maleic anhydride in different organic solvents

Data on corresponding solid–liquid equilibrium of maleic anhydride in different organic solvents are essential for industrial design and further theoretical studies. In this study, the solubilities of maleic anhydride were measured in DMF, methanol, acetic acid, acetonitrile, acetone, ethyl acetate, 2-propanol and n-butyl alcohol with the temperature range of 278.15–323.15 K by the analytical stirred-flask method under atmospheric pressure. The experiment results indicated that the solubility of maleic anhydride was highest in DMF and followed by methanol, acetic acid, acetonitrile, acetone, ethyl acetate, 2-propanol and n-butyl alcohol. For the temperature range investigated, the solubilities of maleic anhydride in the organic solvents increased with increasing temperature. Results of these measurements were well-correlated with the modified Apelblat equation, the Buchowski–Ksiazaczak λh equation and the van’t Hoff equation. The calculated solubilities showed good agreement with the experimental data. The modified Apelblat equation was found to regress the solubility data is higher accuracy than the Buchowski–Ksiazaczak λh equation. The experimental data and model parameters would be useful for optimizing the process of purification of maleic anhydride in industry.